All valid points. I mean it is mind boggling, truly mind boggling, the more Cindy tries to to shed light on the relationship she and KC shared the more questions arise. The fact that she supposedly knew but did not confront KC about being pregnant is absurd, particularly if they had as loving a relationship as Cindy would have us believe. As you mention, prenatal care is extremely important for mother and child, it is one thing that Cindy did not come to her daughter to guide her as a mother, but that she as a nurse would allow her daughter to risk her own health and that of her grandchild is almost unbelieveable. With this in mind I am not sure Cindy would have made any effort to guide her daughter to, or provide her with birth control. I get the feeling Cindy would have told Casey to take care of that herself as some sort of passive punishment for being sexually active.
If Cindy was really confident in KC and her innocence then she would have no need to white wash her past. The lack of honesty that this family has lived with is startling and sad.